class Base2 {
    public void testA() {
        System.out.println("testA()");
    }
}

class Derived2 extends Base2{
    public void testB(){
        System.out.println(" testB()");
    }
    public void testA(){
        System.out.println("derived：testA()");
    }

    public void testC(){
     this.testA();
     super.testA();//加上super访问父类
     this.testB();  //this访问子类
    }
}
public class test4 {
    public static void main(String[] args) {
        Derived2 derived2=new Derived2();
        derived2.testC();
    }
}
